Carbureter.



Patented July 15, 193

2 SHEETS-SHEBTL :i l l A. B. BROWNE.

GARBURETER.

AYPLIOATION FILED NOV. l, 1911.

A. B. BROWNE.

GARBURBTBR. APPLICATION FILED NOV. 1, 1911.

' Patented July 15, 1913.

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ARTHUR BENJAMIN BROWNE,

Moo afiaiifiiaav Saa Specification of Letters Patent. y

OF BRANFORD. CONNECTICU' i.

CARBURETER. f:

Patented July 15, 1913.

-vApplca'tion filed Novembei'1.l9l1. Serial 110.4653008.,

Be it known that l` ARTHUR Bitxnuix BRowNE, a citizen of the United lqtates. re-

" siding at Branford, in the county ot` New Carbureters llaveii and State of Connecticut, have invented a new and useful Improvement in and I do hereby declare the following, when taken iii connection with vthe accompanyingT drawings and the letters of reference marked thereon, to bea full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent, ini Figure l a side view of a carbureter constructed inaccordance with my invention.

Fig. 2 a longitudinal sectional View of the same. Fig. 3 a' top or plan view.` a'sectional view on the line a-b of Fig. 4 Fig. 3. Fig. 5 a sectional yview illustrating a mod ified form of carbureter embodying my invention.

My invention relates to an improvement in carbureters for supplying internal combustion engines with a combustible mixture of vapor-gas and air; and the vobject is to provide means whereby a closer regulation of the relative proportions of gas and air may be' maintained, irrespective of varying engine speeds, than is at present possible.

My invention more especially applies to that form of carbureter wherein a mixing chamber is supplied with air through two openings or passages, one of which, usually termed th; primary inlet passage, is of permanent area', and the other, usually termed the auxiliary inlet, is of variable area. In this form of carbureter it is customary to vary the area of the auxiliary opening by means of a valve, or other closure, which is actuated by the partial vacuum created within the mixing chamber by the suction of the engine.` In carbureters of this construction it is found that the auxiliary valve openstoo far, admitting too much air at high engine speeds. In my device I so form and so control the auxiliary area that, irre- Aspective of the amount of travel or-movement to which the closure is subjected, thev exposed auxiliary area is at all times that necessary for the admittance of the proper amount of air to make a substantially quan- Y y titative mixture.

In 'carrying out my invention, I make use of the fact that diering velocities of the air within the primary inlet passage, occa.- .sion greater differences of pressure Within fsaid primar inlet which hear a more detii nite relation vto the flow of fuel than do the the mixing chamber. so that' .by directly utilizing the reduction of pressure lcaused h y this velocity within said primary inlet, for the modification of the area of the auxiliary inlet. and preferably as well to cause a flow of fuel` I secure closer and more positive possible.

bureters of convenient the principles of myiiivention, although material changes may be iiiade in the form and arrangement of the different parts, and I do not confine myself to the specific forms shown.

In Figs. 1 to l I show a primary Venturi tube 2, and a .mixing chamber 3 the opening of which is controlled by a, throttle 4 which may be of any approved construction. In the IVenturi tube 2 is inserted a fuel jet. 5. said jet heilig controlled by a needle gasolene, passes to this needle valve through a tube 7 from a reservoir 8 which may also be of any approved form. As herein shown, this reservoir is adapted to have gasolene enter through a valve 9 which is controlled by a oat 10, through any linkage. In the casing forming this mixing chamber 3 is an auxiliary openingll to the atmosphere. The area of this opening is cont-rolled by a valve 12 which is mounted on a stem 13 and normally held ina position closing the opening 11 by the spiral spring 14, the tension of which may be adjusted by a thumb nut. 15. The lower end of the stem 13 extends into a vacuum chamber 16 and is attachedto a flexible diaphragm 17 of any suitable material. The diaphragm 17 is secured near its outer edges and forms the upper wall of the vacuum "chamber 16. Leading from this vacuum chamber zle 18-extending into the Venturi erably in approxi-mate line with the jetT): To prevent a decrease of pressure on the topof the diaphragm by the velocity of the air passing into the opening 11, the stem 13 is passed through a which openings 20 communicate with the atmosphere.

During the suction stroke. of the motorwhich the apparatus is supplying, the veinclusive of the. drawin tube prefthe end of differing degrees of vacuum .formed within regulation of the mixture than isjotherwise valve 6. Liquid fuel, such as plate 19` below The accompanying `drawings .show car-.fv

design embodying:l

v yus air inlet 1nthe form o a I als ordinary form of r is a nozlocity of the air passing through the Venturi tube 2 causes'a certain reduction of pressure within said tube, resulting in a flow of liquid throughthe jettpand, at the same 5 time. occasioning acorresponding diminution of' pressure-within the vacuum cham perl6, when the atmospheric pressure upon the diaphragml 17 causes'the valve 12 to 'open an amount determined by the unit detlection of the spring 14, thereby admitting a certain amount of air to the mixing chamber 3. As the speed of the motor increases, the increased vvelocity of air through the -Venturi causes a roportional increase of pressure on the diaphragm 17. which. in turn, causes a proportional deflection of the spring 14 permitting the valve 12 to open a proportional amount of its travel. The va ve 12 is so formed that the annular area 'between it and the opening 11 is enlarged, as v the valve is depressed by the diaphragm,

a suicient `amount to provide, when the valve is in any osition, an inlet area which,

together with t e1 area of the Venturi 2 at the point of the` Jfuel jet `5, shall cause the velocity of the air passing the fuel jet 5, to besuch as shall. mspirate an amount of liquid fuel directly proportional to the quantity of air entering the mixing chamber 3. To make the accomplishment-of this result practical, the valve 12 shouldV preferably move to a certain definite position of openl ing for any given engine speed and. this may be best accomplished by the arangement of parts shown in Fig. 2, in @which construction the travel of the valve-is directly modified by the vvelocity vwith which the lncoming air passes" the nozzle 18. 'i It the tension and deliectiono the spring 14: 40 is properly adjusted with relation to the form of the valve'l2l,a's the-speed increases the valve l12 will be opened to a greater; de-

ee; but to Whatevelfp'oint it is opened. as before stated, the veloeitv` of the air over the fuel jet in the main inlet passage will vbe such that at all times a corresponding amount of fuel is inspirated.

Instead of forming the valve with a curved surface, the valve-seat may be curved las shovvn in Fig. 5. ln this form of my invention the opening into the mixing chamber 3 has a curved seat 21 while the valvb 22 is a Hat disk of uniform diameter and is `mounted at the end of a spindle 23 guided vthe principles of m` v invention, but for the reasons hereinbefore set forth, I prefer to control the movement of the valve method shown in Fig. 2.

1. A' carbureter having a chamber profr 65 vided with a primary air inlet and an auxiliary air inlet of variable area, means for adv mitt-ing `fuel into said chamber, and means responsiveto'the reduction of pressure created wit-hin the primary air inlet .by the velocity of the air in its passage through said primary air inlet, for varying the areal of j the auxiliary air inlet. Y

2. A carbureter having a mixingchanr ber provided with a primary airinlet and an auxiliary air inlet of variable area, a. fuel duct opening into said primary air inlet, a. l vacuum chamber havin no communicationd with said mixing chantier except. through the said primaryv air inlet, in which said' 80 vacuumv chamber a reduction of pressure caused by the velocity of the air'within the said lprimary air inlet. is made'to modify the area of the auxiliary air inlet.

3. A carbureter having a mixing chamber provided with a primary air inlet and an auxiliary air inlet of variable area, a Jfuel duct opening into the said primary air inlet, a vacuum chamberV havingno communication with said mixing chamber except through .the primary air inlet, a diaphragm vcontrolled by Jvariations of pressure 1n the said vacuum chamber and operating to vary the area of the auxiliary air inlet.

In testimony whereof, I have signed this specification in the presence of two sub. serihing witnesses.

ARTHUR BENJAMIN'BROWNE. Witnesses: i

' W. S. Woon,

C. W. Foo'rn.

bythe y 

